For the crank, just take off the big ring and buy a bashguard. You don't need a new crank.
More travel...depending on how much travel you want, you may need a new bike. You can safely add maybe 20-30mm of travel up front, any more than that and the geometry will get weird, plus your frame's headtube might not be equipped to handle it.
Front derailleur you won't notice a difference. Don't bother.
Swap the stem if you don't fit on the bike now and want a more upright riding position.

Then save for a new bike, rather than trying to make this one into something it's not.